The present invention relates to a housing for electrical equipment. The housing includes side walls, ventilation openings and cover plates for closing the ventilation openings.
The present invention is used primarily for housings made of steel sheet for independent table model units for use in industrial electronic systems.
It is known to permanently provide a certain number of ventilation openings, depending on the particular model, in housings for electrical equipment. These openings cannot be closed again and thus it must be determined before the housings are equipped how much cooling is to be provided in the individual regions of the housing for the highly sensitive electronic units. Specifically, however, if the housings are equipped individually, it may happen that none of the embodiments on the market meets the particular requirements. Another drawback is that, once the housing has been equipped, it is no longer possible to consider subsequent changes, since the making of additional ventilation holes produces dust and chips which penetrate into the interior of the housing and thus may interfere with the proper operation of the electronic device. For example, retrofitting from convection cooling to fan cooling or vice versa creates difficulties since ventilation openings disposed in the side walls cause the generally horizontally arranged blowers to suck in the wrong air through these ventilation openings. In contrast, for good fan cooling it would be appropriate to suck in the cooling air only from the front or the bottom and let it be discharged at the rear or through the cover plate of the housing. Makeshift solutions of, for example, closing the annoying ventilation openings by gluing something over them, generally do not meet safety regulations and are thus not permitted.
A component carrier is known which has side walls and a cover and bottom that are provided with air ventilation holes. Guide rails for circuit boards that are equipped with electronic components and can be inserted one next to the other are provided at the top and bottom. With the aid of pressure and screw lock mechanisms, fittings are fastened to those guide rails that do not carry any circuit boards to close the air ventilation holes in these bottom regions and thus influence the stream of cooling air in the direction toward the existing circuit boards (German Unexamined Published Patent Application DE-OS 3,922,188). However, this proposal is not suitable for influencing the cooling air to be supplied from the outside to housing interiors.